Radiotelegraphy



L. F. FULLER.

RADIOTELEGRAPHY.

APPLICATION FILED APR. I4, I9I9.

41535229144:. ana Nov. 9, 1920.

W I TN ESS IN VEN TOR MS A TTOR NE YS LEONARD F. FULLER, `(11F PALOALTO, CALIFORNIA, ASSIGNOR T0 AUGUSTUS TAYLUR, '0F SAN FRANCISCO,CALIFORNIA. i

p BADIOTELEGRAPHY.

Speccaton ofvLetters Patent. Patented NOV. 9, 1920 Application filedApril 14, 1919., Serial N0. 289,947.

To all whom, t lmay conce/rn.'

Be it known that I, LEONARD F. FULLER, a citizen of the United States,and a resident or' YPalo Alto, county of Santa Clara, and State ofCalifornia, have invented cer tain new and useful Improvements inRadiotelegraphy of which the ollowing is a specification. y Theinvention relates to radio telegraphy transmission systems andparticularly toY a system employing a plurality ot Poulsen a rcconverters.A

An object ot the invention is to provide a radio telegraphy transmissionsystem embodying a plurality ot' arc 'which each arc may be operatedseparately or in whichthe arcs may be coupled and operated in multiple.

Another object of the invention is to provide a Inultiplearetransmission system signaling system.`

The invention possesses other advantageous features, some of which, withthe foregoing, will be set forth at length in the ollowing descriptionwhere I shall outline 1n full, that form ot the invention which I haveselected. for illustration 'in the drawing accompanying and tormlng partot' the present specifica-tion. The drawlng 1s a diagrammaticrepresentation ot' one form ot transmission system of my invention, but

it is to be understood that I do not limit` myself tovsuch form ofsystem.

Radio' telegraphy transmission systems employing the parallel operationof Poulsen arc converters have been proposed heretofore, butcas far as Iam aware, all of these prior systems propose the employmentl ot two ormore arcs operating on one antenna so that the arcs may system. VIn thesystem of my invention, an antenna system is provided for each arc, beemployed separately or in multiple. 'In accordance with my system,facomplete transmitting set may beconnected to each antenna, so thatdiplex sending will be possible by operating thel two sets on differentwave lengths. IVhen transmission to a particular point becomes diiiilcult or when it is desirable to extend the transmitting range of thestation, the two arcs may be operated in parallel, with a very 'simpleswitching arrangement, t o radiate energy from the two antennaesimultaneously. `In accordance with my invention signaling may beaccomplished by al- 'converters, in x ternately throwing the currents inthe two antennae into and out of phase. i antennae are very closetogether, so that w'henthecurrents aire in phase, theirenergies areadded and signals are transmitted, and when they are out ot phase, thewaves radiated from the two antennae produce complete interference sothat no energy reaches the receiving station.

The system shown diagrammatically in vthe drawing comprises two Poulsenarc converters 2, 'fed by the D. C. generators 3 through the choke coils4. One side of each arc .is grounded and the other side of each arc 1sconnected respectively to the antennae o-G through the variable loadinginductors 7 8. The two transmitting systems may be adjusted fordifferent -wave lengths and diplex signaling may be accomplished, andfor this purpose each transmitting system vis provided with anindependent signaling key of any suitable form, such as the keys 12and-13 arranged to respectively short circuit a few turns ot' theloading coils Tand 8..

lVhen it is desired to transmit with increased power upon a given wavelength, the arcs are operated in multiple.` Inductively connected to theloading coils 7 and 8 'and connected in series in the circuit 1/1, are

the inductors 15 and 16,. The circuit 14 contains a signaling `key 17,and-preferably a variable condenser 18, -although the dondenser may beomitted when desired and the coupling circuit Ithereby changed from ayresonant circuit to a nonres'onant circuit. lVheu the condenser 18 1somitted the coils 7-15 and 816 should be more closely cou- A pled thanwhen the condenser is employed,`

and the polarity otthe inductors 15-16 must be reversed with respect toeach other.

rl`he two antenna systems are disposed so that there is a'slightelectrostatic coupling between them. This coupling usually exists inproper degree when the two antennae-are erected on different towersystems, but are brought to the same radio station building. 1V hen thecondenser 18 is used, the condenser and the inductances 15A and 16 areso adjusted that the coupling circuit has the same frequency otoscillation as vthe antenna circuits, which are adjusted to the sametrequency when multiple-arrsending is to be employed.- vWith theseconditions of coupling existingthe antenna currents will be roo so thatpractically no energy Willbe radiated `from the station. When the key 17is closed.,

the antenna currents arevbrought into phase When the direction of curent flow 1n coils 7-15 and 8-16 is such t at an increasing current inone antenna Will yinduce an in-l tore, accomplished' by closing andopeningI the key lwhich causes the antenna, currents to be alternatelythrown into phase and into phase opposition? it cla1m:- 1. A radiotelegraphyy transmission system, comprising a plurality ofadjacenttransmission systems, each having an `arc converter and an antenna, andmeans for coupling said adjacent systems together.

Q -A radio telegraphy transmission system, rcoinprising a plurality ofadjacentl transmission systems, each having an are converter, an antennaand an antenna loading coil, and a circuit coupling said loading coilstogether.

3. A .radio telegraphy transmission system, -comprising a plurality' ofadjacent transmission systems, each having yan arc converter andanantenna,'a circuit couplingv said adjacent vsystems together,arnilineansv for interrupting and establishing the flow of currentthrough said circuit.

4. A radio telegraphy transmission systeni, comprisinga plurality ost'adjacent transmission' systems', each having an Yantenna so disposedthat an electrostatic conday of April, 1919.

maaien y 5. A radio telegraphy transmission sys- "tem, comprising a'plurality of adjacent transmission systems, each having an antenna,anantenna loading coil and an arc "converterva circuit coupling saidloading coils, and means for establishing and interrupting thel'low vofcurrent in said circuit.

6. y .A radio 1 telegraphy transmission system, comprising a' ,pluralityof adjacent transmission systems, each havlng an an-j in said circuit.

7. A radio ,telegraphy transmission system, comprising Ia plurality ofarc converters, a separate antenna system for each con'- verter, andacircuit electromagnetically coupling said antenna systems.

8. The method of' radio' signaling, Which consists in establishing twoantenna currents and throwing said currents alternately into and out of.phase. f

9. 'lthe method of radio signaling, which consists in establishing twoantenna currents of equal frequency and value and throwing saidvvcurrents alternately into phase and phase opposition.

lin testimony Whereoflt havehereunto set my hand at PaloAlto,Calii:`ornia, this 5th LEUNARD F. FULLER.

fvtenna.system, said antennasystems beingelectrostatically coupled, acircuit coupling said antenna systems, and means for estab-` lishing andinterrupting the flow of current

